Please refrain from "hijacking" existing threads with tangent or off-topic questions. You can create new threads for new questions using the "New Thread" button on the upper left of the page.
The circuit posted in the original thread should work.
You may also want to take a look at Dave Johnson's website at www.discovercircuits.com. Click on the schematic tab on the home page to go to the section containing a great variety of circuits for different applications. You can use the search box to find the circuits that can give you some ideas on how others have solved the problem of monitoring water levels.